Various types of optical displays are commonly used in a wide variety of applications. In many applications, the reliability of the display is of critical importance. For example, in vehicles such as aircraft, optical displays can be used to provide important performance and safety information to the operator. In these applications, the critical nature of the information provided to operator demands high performance and reliability from the optical display.
Unfortunately, many optical display systems have limited reliability. In these displays, the failure of one critical part can render the entire display inoperable. For many applications, this can lead to unacceptably high failure rates. For example, electronic displays are commonly used in aircraft to provide a wide range of critical information to the crew. In such aircraft applications, the reliability of the display is of utmost importance, and even very low failure rates can be unacceptable.
One area where optical displays can exhibit failure is in the lamp illuminating the display. Display lamps can fail in many ways. As one example failure mode, typical fluorescent lamps can fail when one of the cathodes providing electrical charge to the lamp breaks down. When the cathode begins to fail, the performance of the lamp can quickly degrade and in many cases is rendered totally inoperable. In many applications, even a partial degradation of lamp performance can unacceptably degrade the performance of the display. Furthermore, in most cases a complete failure in the lamp illuminating the display will render the display totally inoperable. Again, in applications such as aircraft displays, such failures can be unacceptable even at very low failure rates.
Thus, what is needed is an improved lamp driver system that provides the improved performance and reliability needed for critical applications.